Ohio Geological Survey Bulletins
Report of the Geological Survey of OhioDr. J. S. Newberry, State Geologist (volumes 1-4)Dr. Edward Orton, State Geologist (volumes 5-11) Published by authority of the Legislature of OhioColumbus, Ohio :…
Trilobite Web sites
triloworld - A collection of information on trilobitesWestern Trilobite Association - Group of dedicated amateur and professional trilobite collectors whose focus is on western North Americahttp://www.trilobites.info/ - Trilobite Reference SitePaleoBiology…